Re: gettimeofday() vs. /proc/rtc

yodaiken@chelm.cs.nmt.edu
Sun, 19 Jul 1998 17:17:15 -0600

On Sun, Jul 19, 1998 at 11:37:49AM -0700, Truxton Fulton wrote:
> It takes 1000 microseconds to read /proc/rtc, whereas gettimeofday()
> takes only 15 microseconds to complete. Both of these are way too
> long. On my 133 Mhz 486, it seems like there should be a fine grained
> timer that takes less than 1 microsecond to read... any suggestions?

Reading the 8253 can take up to 15microseconds on every x86 PC I have
tested, including 333Mhz PIIs. Linux is good, but it cannot make antique
hardware speed up.

-- 


---------------------------------
Victor Yodaiken
Department of Computer Science
New Mexico Institute of Mining and Technology
Socorro NM 87801
Homepage		http://www.cs.nmt.edu/~yodaiken
PowerPC Linux page	http://linuxppc.cs.nmt.edu
Real-Time Page		http://rtlinux.org




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